Does your best friend always get stoned at parties? Is your parent an alcoholic? Teen Vogue reports on how to cope if there's an addict in your life.

Three years ago, when Rachel got her freshman dorm assignment in the mail, the New Jersey teen excitedly logged on to Facebook to look up her new college roommate, Eleanor. "She definitely seemed like that perfect, blonde, athletic, popular girl," says Rachel, now 20.

But just a few weeks into their first semester, Eleanor, who had been recruited for the school's soccer team, quit the sport when practice sessions interfered with her ability to party. Still, Rachel says she didn't think Eleanor had a serious problem until the start of their sophomore year. "She'd go out a lot and get way more drunk than anyone else," Rachel recalls. It also became difficult to be her roommate. "If we all went out, I'd go back to my room and go to sleep, and then she'd come in hours later with a guy—or just drunk and angry." Rachel and her friends tried to talk to Eleanor several times about her drinking, but they couldn't get through to her. Rachel says they didn't know what to do.

According to the Substance Abuse and Mental Health Services Administration's National Survey on Drug Use and Health, 23.5 million people ages twelve or older needed treatment for an illicit drug or alcohol abuse problem in 2009—and that counts only those who sought professional help. Far more struggle with addiction issues in private. "Addiction is so common that, unfortunately, you could say it's normal," says psychologist and substance abuse specialist Patricia O'Gorman, Ph.D. "More kids are dealing with it in their lives than not." And while chemical dependency takes an obvious toll on those struggling with it, it also affects everyone around them. Indeed, when you're close to someone—be it a friend, significant other, or family member—who's regularly drunk or high, it can be difficult to know how to deal.

Eighteen-year-old Annie, from Virginia, can relate to that feeling of helplessness. When she was thirteen, her then-boyfriend, Matt, started heading in a destructive direction. "A year into our relationship, his parents filed for divorce, and that's when things took a wrong turn," she says. "The first time we broke up was because he wanted to try weed and I wasn't game. After that, things really took off. Every day he was stoned, and soon he was drinking and partying with his friends—and some of their parents too."

Annie says Matt's habits led to many issues between them. "I'd spend hours online trying to find ways to help him with his problems," she says. "When our relationship came into question, he was always confused. If he hadn't been high, his mind wouldn't have been so foggy. Being thrown on this emotional roller coaster made me feel like I was taking drugs myself."

One of the challenges of having a parent, friend, or boyfriend who's battling an addiction is that the person often doesn't remember his or her harmful behavior the next day, according to O'Gorman. "It's common for addicts to go in and out of states of blackout or not remember times they were mean to you," she notes. Rachel says this was the case with Eleanor, but when friends confronted her about her angry behavior the day after she'd been out drinking, she'd deny or downplay it.

"We know from research that kids who drink too much think their friends drink a lot too," O'Gorman says. "So one of the things you can do in that situation is just tell your friends that you're worried they're drinking too much. As simple as that sounds, it helps puncture this balloon of 'I'm doing what everyone's doing.' "

Rachel says things with Eleanor came to a head at the end of their sophomore year. Eleanor was arrested for trying to buy alcohol underage. She hid the truth from her mom for a while but finally, after a night of drinking, called her to confess that she had a problem. Eleanor's mom immediately texted Rachel. "I told her mom, 'It's great that Eleanor opened up to you because we're all concerned. It has become a problem,' " says Rachel, who was relieved that Eleanor had come clean, even if it was when she was drunk. "If she had waited until the next morning, she probably wouldn't have done it and instead just said, 'Oh, I'm fine.' "

Lindsay, seventeen, from Illinois, faced a similar situation with her best friend, Jake. When they met, she says, "I knew he sometimes smoked marijuana with friends and maybe had a beer or two, but nothing too atypical for a high school student." However, what started as an occasional night of partying led to a downward spiral for Jake. "His recreational habit of smoking a joint once a week turned into an addiction that led to cocaine and heroin," she says. "He even moved out of his parents' house."

Lindsay says she felt lost while watching her friend fall into chemical dependence. "I almost always turn to my parents when I need help, but given that they strongly disliked him, I felt I would get an 'I told you so' response. My closest friends didn't like him either. So I never was able to turn to anyone for guidance."

Understanding the physical and psychological issues tied into addiction doesn't always make dealing with it easy, according to O'Gorman. "This is a disease that really affects behavior," she explains. Annie says she saw drastic swings in Matt's actions and reactions while they were dating. "I never knew which version of him I would get," she says. "He had such an impact on me that I would get really sad and think poorly of myself."

If the person you care about is behaving recklessly either emotionally or physically, you need to protect yourself. "Keep boundaries," advises Washington, D.C.-based psychologist Jill Weber, Ph.D. Suggesting social activities that don't involve drinking or drugs is an easy way to spend time with the addict in your life. "Focusing on healthy alternatives—like hanging out at Starbucks or going for a hike or shopping—is a good strategy," agrees O'Gorman. If your friend or loved one is living with an alcoholic or addict parent or guardian, you can help out by inviting him or her to spend time with your family. "Make your home available," says O'Gorman. "Having a safe place to go is important."

One of the hardest things about loving someone who's an addict is not taking his or her behaviors to heart. "Girls tend to take these things very personally," notes O'Gorman. "How can you not, when he or she says or does something that is very hurtful to you? I mean, this is your boyfriend, this is your best friend, this is your mom." If you're close to someone who's struggling, it's important that you have a private space to share and talk about it. Experts like Weber and O'Gorman suggest looking for support groups, like Alateen, which is part of the Al-Anon program, an international organization that helps families and friends of alcoholics. (For more info, go to al-anon.alateen.org.)

Gina*, a seventeen-year-old from Kentucky, who grew up with an alcoholic father, says attending Alateen meetings allowed her to deal with how her dad's illness has affected her—even years after she and her sisters were placed in an adoptive home. "I learned that I was still reacting to the situation," she says. "But I'm learning now to not take it as personally." However, it can be difficult if the loved one doesn't want to change or get better. "Recognize that you are not responsible for an addict's behavior and you can't fix it for them," says Weber. "Recovery from addiction is only successful when the person wants and accepts help."

Unfortunately, the reality is that many don't. Eighteen-year-old Beth, from New Jersey, is dealing with this situation now. A few years ago, one of her best friends, Jen, started dating a new guy, who hung with a bad crowd. Suddenly, Jen started regularly ditching plans with Beth. When Beth confronted her, Jen revealed she was addicted to heroin—and had no intention of stopping. "I was floored," Beth remembers. "She wasn't the same person I used to have sleepovers with. I told her she needed to stop, but she didn't want to listen and started screaming at me." Though Jen has been in and out of rehab, she remains addicted to heroin—and currently isn't speaking to Beth. "It affects me every day because I feel like I could do something more to help her, even though I know I can't."

Indeed, it's impossible to force people to seek help if they don't want it, but if your loved one decides to get healthy, your support can make a big difference. Though Annie broke up with Matt, they've remained in touch as he strives to get better. "Even though things didn't work out between us romantically, I still want to help him have the best life he can," she says, adding that she realizes only Matt has the power to change his situation.

Rachel's story ends on a hopeful note as well. Her roommate, Eleanor, did slip up a few times after admitting she was an alcoholic, but she eventually joined Alcoholics Anonymous and has been working on her sobriety for over a year. Rachel and her friends went to Eleanor's first off-campus AA meeting to support her. "Not to sound corny," Rachel says, "but [watching her go through this] has shown me what matters most. And how meaningful friendships can actually be."